JPH073191B2 - Centrifugal governor of belt timing transmission diesel engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a diesel engine in which the operation of a fuel injection pump or the like is performed at a predetermined timing by belt transmission, and the rotation of the engine is based on the centrifugal force of a governor weight. Concerning the governor to control the constant.

[Basic Structure] The basic structure of the centrifugal governor of the belt timing transmission diesel engine, which is the premise of the present invention, is as follows.

For example, as shown in FIG. 1, FIG. 6 or FIG. 7, a pump housing 3 is fixedly installed on a lateral side of a cylinder block 2 of a diesel engine 1, and a fuel injection pump 4 and a fuel injection pump are installed in the pump housing 3. The camshaft 5 is provided, and the timing belt case 6 is fixed to the front surfaces of the cylinder block 2 and the pump housing 3, and the fuel injection camshaft 5 is attached to the crankshaft 7 in the timing belt case 6 via the timing transmission belt 45. So that the governor spring 12 and the governor weight 13 are linked to the fuel metering device 9 of the fuel injection pump 4 via the governor lever 11 of the centrifugal governor 10 so that the governor lever 11 is received at the full load position by the fuel restrictor 52. It is configured in.

The governor lever 11 may be of a single type or a double type.

[Prior Art] As a timing transmission device for a diesel engine, one disclosed in Japanese Patent Publication No. 55-51086 (hereinafter referred to as "conventional example 1") and one disclosed in Japanese Utility Model Publication No. 63-14031. (Hereinafter referred to as "conventional example 2").

In the conventional example 1 as shown by the solid line in FIG. 6 and in the conventional example 2 as shown by the solid line in FIG. 7, the fuel injection camshaft input wheel 16 is composed of gears, and the conventional diesel engine in general. Similarly, this is composed of gears.

[Problems to be Solved by the Invention] Therefore, the above-mentioned conventional technique 1 has the following problems.

High accuracy is required for the arrangement of the crankshaft and the fuel injection cam shaft 5, and the manufacturing is troublesome and the manufacturing cost is high.

In order to solve the above problem, it is conceivable that the fuel injection cam shaft input wheel 16 is formed of a pulley and the timing transmission device 8 is of a belt transmission type.

In the belt transmission type timing transmission device 8, since the mechanical strength of the timing belt 45 is small, the contact area between the timing belt 45 and the fuel injection cam shaft input wheel 16 is widened to increase the unit area of the timing belt 45. The load on the fuel injection camshaft input wheel 16 must be increased for this reason.

Further, since the strength of the timing belt 45 decreases due to the permeation of oil, it is necessary to prevent the oil from scattering from the governor 10. Therefore, the governor 10 and the timing transmission 8 must be sealed. I won't.

Prototype examples 1 and 2 in which the timing transmission device 8 of the conventional examples 1 and 2 is improved to a belt transmission type are shown by two-dot chain lines in FIGS. 6 and 7.

As shown in FIG. 6, in Prototype Example 1, which is an improvement over Conventional Example 1, the interference between the large diameter fuel injection camshaft input wheel 16 and the governor 10 is avoided, and the oil scattering from the governor 10 to the timing belt 45 is prevented. In order to prevent it, the following structure is unavoidable.

That is, in the basic structure, the governor case 55 must be interposed between the crankcase / pump housing 3 and the timing belt case 6, and the governor lever 11, the governor spring 12, and the governor weight 13 must be provided in the governor case 55. In this case, the fuel limiter 52 is covered by the timing belt case 6.

For this reason, the following problems 1 to 3 occur in the first trial example.

Since the governor case 55 and the timing belt case 6 are sequentially arranged in front of the crankcase and the pump housing 3, the total length of the engine 1 becomes long.

Since it is necessary to provide two types of governor case 55 and timing belt case 6 in the pump housing 3, the manufacturing cost becomes high.

Fuel limiter unless the timing belt case 6 is removed
Since 52 cannot be adjusted, the adjustment is troublesome.

On the other hand, the trial example 2 which is an improvement of the conventional example 2 shown in FIG. 7 is forced to have the following structure for the same reason as the above-mentioned conventional example 1.

In other words, in the basic structure of trial example 2, the fuel injection cam shaft input wheel 16 must be arranged in front of the fuel limiter 52 arranged on the timing belt case 6 while avoiding interference with the fuel limiter 52.

For this reason, the following problems / problems occur in the second prototype.

Since the fuel injection camshaft input wheel 16 and the timing belt 45 need to be provided separately from the fuel limiter 52 in the timing belt case 6, the timing belt case 6 becomes thicker, so the engine 1
The total length of

Since the tip of the governor lever 11 that contacts the fuel restrictor 52 enters the timing belt case 6, the governor lever 11 is placed inside the timing belt case 6 in order to prevent oil from scattering to the timing belt 45 from here. Since the oil sealing wall 56 that covers the movement region of the tip of the engine must be formed, the structure of the engine 1 is complicated, the manufacturing cost is high, and the maintenance is troublesome.

The present invention reduces the manufacturing cost of an engine, downsizes the engine, facilitates the adjustment operation of the fuel limiter, and facilitates maintenance of the engine. It is an issue.

[Means for Solving the Problems] (First Invention) The first invention is characterized in that, in the basic structure, the governor is arranged as follows.

For example, as shown in FIGS. 1A to 1C, the governor lever 11, the governor spring 12, and the governor weight 13 are provided in the pump housing 3, and the fuel limiter 52 is provided outside the timing belt case 6 in the pump housing 3. It is pierced through and supported to be adjustable forward and backward.

(Second invention) As shown in FIG. 5, for example, the second invention is the same as the first invention, except that an oil level gauge 53 and an oil drain hole are provided in a lower portion of the pump housing 3 of the diesel engine 1.
54 is arranged.

[Effects] (First Invention) The first invention has the following effects.

Since the timing belt transmission is used as the timing transmission, compared to the timing gear transmission, the crankshaft and the fuel injection cam shaft need not be arranged with high precision, and the manufacturing is simple and the manufacturing cost can be reduced. You can

Since only the timing belt case is arranged on the front surfaces of the crankcase and the pump housing, and it is not necessary to separately provide the governor case 55 shown in FIG. 6, the overall length of the engine can be shortened.

Since the governor case 55 shown in FIG. 6 is unnecessary, the manufacturing cost can be reduced.

Since the fuel limiter can be adjusted as it is from outside the timing belt case without removing the timing belt case, the adjustment operation can be easily performed.

Since the fuel injection camshaft input wheel and the timing belt can be installed close to the front wall of the pump housing without interfering with the fuel limiter and governor, the timing belt case can be made thinner. The total length of the engine can be shortened.

Since the fuel limiter is arranged in the pump housing, and the governor lever for contacting the fuel limiter can be arranged in the pump housing, the front wall of the pump housing can be directly used as an oil sealing wall, and the engine structure is simple and its manufacturing cost is low. It is low and maintenance is easy.

(Second Invention) The second invention has the following effects in addition to the effects of the first invention.

Maintenance of fuel injection pump, confirmation of oil amount,
Oil can be changed all at once from one side of the engine.

[Embodiment] An embodiment of the present invention will be described with reference to the drawings.

1 to 5 are views for explaining a centrifugal governor of a diesel engine according to an embodiment of the present invention, FIG. 1 (A) is a plan view of the governor, and FIG. 1 (B) is a front view of the governor. , First
FIG. 2C is a side view of the governor, FIGS. 2A to 2F are operation explanatory views of the governor, FIG. 3 is a longitudinal sectional front view of the engine, FIG. 4 is a longitudinal sectional side view of the engine, and FIG. FIG. 5 is a perspective view of the engine.

Reference numeral 1 indicates an engine.

This engine 1 is a secondary combustion chamber type diesel engine, and as shown in FIG. 3, air is supplied from an air cleaner 20 (see FIG. 5) to a surge tank 21, an intake inertia pipe 22, an intake port 23.
The fuel is injected into the cylinder 24 by passing the fuel in the order of, and the fuel is injected by the fuel injection pump 4 under the force of the fuel injection pipe 25 and the fuel injection valve.
The secondary combustion chamber 27 is supplied in the order of 26.

The amount of fuel injected from the fuel injection pump 4 is controlled by the centrifugal governor 10, so that the rotation of the engine 1 can be kept constant at the set value set by the speed control lever 28, regardless of the load fluctuation applied to the engine 1. Has become.

As shown in FIG. 2 (A), the governor 10 is
The tension 30a of the start spring 30 causes the rack pin 29 to be positioned at the increased starting position so that the starting can be easily performed.

As shown in FIG. 2 (B), the speed control lever is operated during low speed operation.
By setting 28 to the low rotation position, the tension 31a of the low rotation governor spring 31 (the high rotation governor spring 35 is in the idle state at the time of low rotation) and the governor force 10a are balanced so that the rack pin 29 Is adjusted appropriately within the fuel control region between the 0/4 load position and the 4/4 load position to keep the rotation of the engine 1 constant according to the value set by the speed control lever 28, regardless of the load variation applied to the engine 1. To maintain.

As shown in FIG. 2 (C), the tension 31a of the low rotation governor spring 31 and the high rotation governor spring 3 are set by setting the speed control lever 28 to the high rotation position during high rotation operation.
The rack pin 29 is appropriately adjusted within the fuel control region by the resultant force of the tension force 35a of 5 and the balance with the governor force 10a, and the rotation of the engine 1 is maintained constant as described above.

As shown in FIG. 2 (D), when the engine 1 is partially loaded, the governor force 10a and the tension 31a are applied.
Or, depending on the balance between 31a and 35a, rack pin 29
Are controlled in the fuel control area.

As shown in FIG. 2 (E), when the overload is applied beyond the full load, the spring lever 32 is largely pulled by the tension 31a or the resultant force of 31a and 35a due to a large decrease in the governor force 10a. However, since the spring lever 32 comes into contact with and is locked by the fuel limiter 52 at the full load position of the rack pin 29, the tension 31a or 35a is not transmitted to the rack lever 48 thereafter, and the rack lever 48 is not transmitted. Is pushed by the elastic force of the torque spring 36.

The spring constant of the torque spring 36 is set to be smaller than the spring constants of both the governor springs 31 and 35, and the amount of change in the governor force 10a after the rack pin 29 exceeds the full load position before it exceeds the full load position. Against rack pin 29
The speed of movement of the engine, that is, the fuel increase speed is slowed down, the engine speed is quickly reduced, the transient period until the engine stall is maintained for a long time, and a time margin for the engine stall avoidance operation can be secured. Has become.

As shown in FIG. 2 (F), when the engine is stopped, if the stop lever 37 is stopped and rotated, the rack pin 29 becomes a long hole.
It can be moved to the stop position along 39.

Since the rack pin 29 can move along the long hole 39 independently of the governor lever 11, the operating force 37a of the stop lever 37 does not receive the resistance of the tensions 31a and 35a of the amount governor springs 31 and 35 and the tension 30a of the start spring 30. The engine 1 can be stopped with a small force enough to withstand.

As shown in FIG. 3, the engine 1 has a cylinder block 2 in which a crankcase is integrally formed under the cylinder 40.
A cylinder head 41 and a head cover 42 are sequentially assembled to the upper part of the above, and a pump housing 3 is formed on the right side of the cylinder block 2.

A fuel injection pump 4 and a fuel injection cam shaft 5 are provided in the pump housing 3, and a timing belt case 6 is provided in front of the crankcase 2 and the pump housing 3 as shown in FIG.
Is fixed, and the timing transmission device 8 is arranged in the timing belt case 6. The timing transmission 8 includes a crankshaft output wheel 43,
A timing belt 45 is wound around the valve operating cam wheel input wheel 44 and the fuel injection camshaft input wheel 16, and the power of the crankshaft 7 is applied to the valve operating camshaft 46 and the fuel is injected as shown in FIG. Cam shaft 5
(See FIG. 3), and these are interlocked at a predetermined timing.

As shown in FIGS. 1 (A) to (C), the centrifugal governor 10
Is a spring lever that constitutes the governor lever 11 on the pivot 47
32 and a rack lever 48 are pivotally supported.

A high rotation spring 35 and a low rotation spring 31 that constitute the governor spring 12 are provided between the spring lever 32 and the speed control lever 28, while the rack lever 48 has a lower end portion at which the governor weight 13 is centrifuged. Fuel injection camshaft 5 by force
A governor sleeve (14) slidably moving along is abutted.

At the upper end of the rack lever 48, a governor link that engages with a rack pin 29 of the fuel metering device 9 of the fuel injection pump 4 through an elongated hole 39.
The front end portion of 49 is pivotally attached, the upper rear surface of the spring lever 32 and the upper front surface of the rack lever 48 are brought into contact with each other, and the rack pin 29 is appropriately adjusted within the fuel control area by the balance between the tension of the governor spring 12 and the governor force. Is adjusted so that the rotation of the engine 1 is kept constant at the set value set by the speed control lever 28, regardless of the load fluctuation applied to the engine 1.

Torque spring 36 on the upper rear surface of spring lever 32
The tip of the push-out pin 51 urged by is projected.

The rack lever 48 of the governor lever 11 is a fuel limiter 52 so that the rack pin 29 can be received at the full load position which is the 4/4 load position.

The governor weight 13 and the governor sleeve 14 are supported by the fuel injection cam shaft 5 in the pump housing 3, the fuel injection cam shaft 5 is also used as a weight drive shaft, and the pump cam shaft input wheel 16 is also used as a weight drive input wheel. Also, the weight drive shaft, the weight drive input wheel, and the bearings of the weight drive shaft are reduced in number, and the structure of the engine 1 is simplified.

The governor lever 11, the governor spring 12, and the governor weight 13 are provided in the pump housing 3 to eliminate the need for a governor case for housing the governor 10, thereby shortening the overall length of the engine 1 and reducing the manufacturing cost. There is.

The fuel limiter 52 is vertically pierced through the upper wall of the pump housing 3 outside the timing belt case 6 to allow forward / backward adjustment, and the fuel limiter 52 can be adjusted without removing the timing belt case 6. The adjustment operation can be simplified.

Further, the fuel limiter 52 is provided outside the timing belt case 6 so that the tip end of the spring lever 32 abutting against the fuel limiter 52 does not need to enter the timing belt case 6, and the fuel injection cam shaft input wheel 16 Further, the timing belt 45 is provided close to the front wall of the pump housing 3 without interfering with the fuel restrictor 53 and the governor 10, so that the timing belt case 6 can be made thin, and at the same time, the pump housing 3 The front wall can be used as it is as an oil sealing wall.

The start spring 30 is directly engaged with the rack pin 29.

As shown in FIG. 5, the pump housing 3 of the engine 1
Oil level gauge 53 and oil drain hole 5 on the lower side of
4, the oil filter 57, the oil supply hole 58, and the water drain hole 59 are arranged to perform maintenance of the fuel injection pump 4, confirmation of the oil amount, oil replacement, oil filter 57 replacement, drainage, etc. from the right side of the engine 1 all at once. I can do it.

Reference numeral 19 in FIG. 1 (C) is a bearing of the fuel injection cam shaft 5. In this embodiment, as shown in FIG. 5, the fuel injection pump 4 is positioned substantially at the center of the cylinder block 2 in the front-rear direction so that the pair of fuel injection pipes 25 can be symmetrically arranged with a short pipe. There is. For this reason, the fuel injection pressure from the pair of fuel injection nozzles 26, 26 provided at the tips thereof is increased, and the injection delay of these is prevented, so that the output performance of the engine can be improved.

[Brief description of drawings]

1 to 5 are views for explaining a centrifugal governor of a diesel engine according to an embodiment of the present invention, FIG. 1 (A) is a plan view of the governor, and FIG. 1 (B) is a front view of the governor. , First
FIG. 2C is a side view of the governor, FIGS. 2A to 2F are operation explanatory views of the governor, FIG. 3 is a longitudinal sectional front view of the engine, FIG. 4 is a longitudinal sectional side view of the engine, and FIG. FIG. 5 is a perspective view of the engine, FIG. 6 is an explanatory view of the prior art 1 and trial example 1, and FIG. 7 is an explanatory view of the prior art 2 and trial example 2. 1 ... Diesel engine, 2 ... Cylinder block,
3 ... Pump housing, 4 ... Fuel injection pump, 5 ...
... Fuel injection cam shaft, 6 ... Timing belt case, 7 ... Crank shaft, 9 ... Fuel metering device, 10 ... Centrifugal governor,
11 …… Governor lever, 12 …… Governor spring, 13 ……
Governor weight, 45 ... Timing belt, 52 ... Fuel limiter, 53 ... Oil level gauge, 54 ... Oil drain hole.

Claims (2)

[Claims] 1. A diesel engine 1 is provided with a pump housing 3 fixed laterally to a cylinder block 2, and a fuel injection pump 4 and a fuel injection cam shaft 5 are provided in the pump housing 3. The cylinder block 2 and the pump housing 3, the timing belt case 6 is fixed to the front surface of the fuel cell 3, and the fuel injection cam shaft 5 is interlockedly connected to the crankshaft 7 via the timing belt 45 in the timing belt case 6. The governor spring 12 and the governor weight 13 are linked to each other via the governor lever 11 of the centrifugal governor 10, and the governor lever 11 is configured to receive the governor lever 11 at the full load position with the fuel limiter 52. The governor lever 11, the governor spring 12, and the governor weight 13 are provided in the pump housing 3, and the fuel restrictor 52 is provided with the timing belt. Centrifugal governor of the belt timing transmitting diesel engines, characterized in that over scan 6 outside by penetrating the pump housing 3 is retractable adjustably supported by. 2. An oil level gauge 53 and an oil drain hole are provided on the lower side of the pump housing 3 of the diesel engine 1.
54. The centrifugal governor for a belt timing transmission diesel engine according to claim 1, wherein 54 is arranged.